F A N And Generator Belt Adjustment; Water Pump Service; Correcting "Ping" In H I G H Compression Engines; Removing Carbon - Cadillac 1937 LaSalle VVI Information

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E N G I N E
As these particles accumulate, the screen
becomes clogged, restricting the flow of o i l and
permitting the settlings in the pan to be stirred
up and carried through the oiling system. • T h i s
material, being grit or metal particles, is highly
abrasive and capable of causing excessive wear in
the engine unless removed.
It is a good plan, when the o i l pan is clown for
periodic cleaning, to inspect the connecting rod
and crankshaft bearings.
Copper mesh air cleaners are used at the crank-
case ventilation air intake on a l l series engines.
On series 37-50, 60, 65, 70 and 75 engines, this
intake is at the engine o i l filler. O n series 37-85
and 90 engines, the intake is a separate housing
at the left front of the engine. T h i s copper
mesh should be cleaned b y submerging in gasoline,
shaking out and dipping in engine oil—every time
the oil pan is cleaned. Series 37-85 and 90 intakes
are thermostatically controlled and care should
be taken not to damage this unit when servicing
the cleaner.
27. F a n a n d G e n e r a t o r B e l t A d j u s t m e n t
The fan belt adjustment on a l l 37-series cars is
the same. A l l belts should be adjusted very
carefully as a slightly loose adjustment will cause
the driven units to slip excessively and to become
noisy at high speeds; a tight adjustment will set
up strains in the belt, shortening its life, and cause
bearing wear.
' T h e fan belt adjustment on a l l series cars is
obtained by loosening the p u l l e y retaining nut
and moving the fan assembly up and down. T h e
belt driving the generator and water pump on
37-50, 60, 65 and 75 cars is adjusted by raising or
lowering the generator on its bracket.
A correctly adjusted belt should have a slight
amount of looseness or slack in it when moved
back and forth with the fingers. A new belt
should always be adjusted tighter than a used
one as it will stretch a little i n service.
28. W a t e r P u m p S e r v i c e
The water pump packings and bearings on a l l
37-series engines are lubricated every 1000 miles
with water pump grease (G-13). T h e only other
attention required by the packings is replacement
when they are worn out.
Disassembly of the series 37-50, 60, 65, 70 and
75 water pump for replacement of parts is per-
formed in the. following manner: (Water p u m p
off car).
1. Remove belt pulley.
2. R e m o v e snap ring.
,3. P u s h impeller rearwards and remove split
washer in back of front bearing.
4. Remove lock spring at front end of rear
bushing.
5. Remove impeller and shaft.
6. Remove rear bushing assembly toward
front, being careful not to lose any parts.
7. Remove front bearing by forcing it out
toward the front.
8. Remove bushing from front bearing.
Reassembly,
in genera], is the reverse of the
disassembly operations. T o assemble the pump
packings on the shaft, install pilot, T o o l N o . J-831,
on the end of the shaft and insert in the p u m p
body. Also w i n d string around the recess near
the end of the shaft to present a smooth surface
on which to slide the packings.
T h e n install the bushings and packings on the
shaft and slide them into position in the pump
housing. C o a t the chevron packings with water
p u m p grease (G-13) before installing. Install the
center bushing with the grooved side toward the
rear packing.
Disassembly of the series 37-85 and 90 water
p u m p will be apparent from the cross section
illustration. P l a t e 39, F i g . 47.
29. C o r r e c t i n g " P i n g " i n H i g h C o m p r e s s i o n
E n g i n e s
The power and efficiency of the engines used
in the 37-series cars are due in large measure to
the high compression ratios of these engines.
T h i s high compression requires, as the price of its
efficiency, careful attention to the problem of
"spark k n o c k " or detonation, and especially,
accurate ignition settings.
Detonation occurring upon rapid acceleration
at low speeds and disappearing at about 15 miles
per hour, is norma).and indicates that the engine
is performing at top efficiency. N o attempt should
be made to eliminate it. Excessive detonation is
abnormal, however, and indicates inefficient opera-
tion and sluggish performance.
T o test a car for detonation, run it at various
speeds i n high gear and accelerate suddenly • to
put the engine, under heavy load. Detonation is
usually apparent only under load. N o t e whether
the " p i n g i n g " is a well-defined tap or knock from
only one or two cylinders or whether it is coming
from a l l cylinders.
If it is evident tftat the pinging occurs only in
one or two cylinders, it m a y be the result of
faulty spark plugs or a hot spot in the combustion
chamber. Check and clean the spark plugs first,
replacing any that are badly worn. If this does
not correct the ping, inspect the combustion
chambers for sharp projections of carbon or
metal which might become overheated and cause
pre-ignition. Remove any such projections.
If the pinging is obviously occurring in all
cylinders, the difficulty will be found in the ignition
t i m i n g adjustment, in the accumulation of carbon,
or improper carburetion. See Plates 40 and 41.
The ignition t i m i n g should be checked to make
sure it is not too far advanced. This can be done
best w i t h the use of a Synchroscope.
30. R e m o v i n g C a r b o n
The most satisfactory way of removing carbon
from automobile engines is by scraping, and this is